* SMART: add eMMC health via sysfs
Read eMMC wear/EOL indicators from /sys/class/block/mmcblk*/device and expose in SMART device list. Includes mocked sysfs tests and UI tweaks for unknown temps.
* small optimizations for emmc scan and parsing
* smart: keep smartctl optional only for Linux hosts with eMMC
* update smart alerts to handle warning state
* refactor: rename binPath to smartctlPath and replace hasSmartctl with smartctlPath checks
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Co-authored-by: henrygd <hank@henrygd.me>
